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Ptychography - New label-free imaging


Ptychography is a novel means of label-free, high-contrast live cell imaging for easy cell tracking and growth analysis, even through plastic cell culture dishes. The high-contrast artefact free images are ideal for cell cycle and cell mass/volume analysis.

Working with PhaseFocus, we report novel applications of ptychography to biological samples, some of which have been published in Nature Scientific Reports 2013 and 2016 and the Journal of Diabetes Research


Phase Focus VL20, VL21 and LiveCyte

  • Ptychography (tie-cog-rafee) is a phase retrieval method which generates high contrast images from label-free cells.
  • Low laser power means that cells can be imaged for greater than 1 week.
  • Cells can be imaged with minimal perturbation-especially useful for primary cells and stem cells.
  • Livecyte includes automatic tracking software for behavioural analysis of hundreds of individual cells within heterogeneous cell populations.


 Phasefocus VL20


Phase focus VL21


Phase focus Livecyte

The ptychographic image has high contrast in comparison to brightfield, differential interference contrast (DIC) and phase contrast imaging.‌

Comparison of imaging modalities

The high contrast allows for clean segmentation of label-free cells for image analysis.

Segmented image

Contact: Peter O'Toole or Rakesh Suman